Fan module

ABSTRACT

A fan module includes a heat transfer unit, a heat radiation unit, and at least one cross-flow fan. The heat radiation unit has an air-in side and an air-out side. The cross-flow fan is located against the heat radiation unit, and includes a frame and a centrifugal fan blade assembly. The frame has an air outlet, a plurality of air inlets, and a plurality of frame sections. The frame sections respectively have a receiving recess therein, and the receiving recesses are communicable with one another to together define a receiving space for receiving the centrifugal fan blade assembly therein. With the above arrangements, the cross-flow fan can create increased air flow volume, the space occupied by the fan module can be reduced, and upgraded heat dissipation performance can be achieved.

FIELD OF THE INVENTION

The present invention relates to a fan module, and more particularly toa fan module that allows at least one cross-flow fan to create largelyincreased air flow volume, has reduced overall volume, provides upgradedheat dissipation performance, and effectively overcomes the problems ofvibration and noise caused by excessively long blades as found in theconventional fan module.

BACKGROUND OF THE INVENTION

Due to the constant progress in the electronic technological fields, thedensity of transistors on various kinds of chips, such as the centralprocessing unit and other executing elements, also increases to enablefaster data processing speed. However, more power is consumed and moreheat is produced by these chips during high-speed operation thereof. Forthe central processing unit to work stably, it has become an importantissue as how to develop a high-efficient heat dissipation means fordissipating the produced heat.

To maintain high-efficient heat dissipating function, it is inevitableto keep increasing the volume and accordingly the weight of the heatdissipation means. However, in the design of currently very popularnotebook computers, tablet computers, smart mobile phones, smarthand-held electronic devices and the like, the limited internal spacethereof is always a bottleneck to the heat dissipation means design.

FIG. 1 shows a conventional fan module 1, which includes a centrifugalfan 10, a heat pipe 11, and a heat radiation unit 12. The conventionalfan module 1 uses the centrifugal fan 10 to produce flowing air, whichcarries away heat absorbed by the heat radiation unit 12 to therebyachieve the purpose of lowering temperature. The performance of the fanmodule 1 is determined by the air pressure and air flow volume producedby the centrifugal fan 10 as well as the area of the heat radiation unit12 available for heat exchange. When the heat radiation unit 12 haslarger heat exchange area by having longer radiation fins, better heatremoval effect can be achieved. However, the long radiating fins tend toincrease the overall volume of the fan module, and a big fan module justfails to meet the demands for compact, slim and light weight notebookcomputers and the like.

To meet the demands for compact, slim, and light weight electronicdevices, all related elements of the electronic devices are minimized indimensions. That is, the centrifugal fan in the fan module must also beminiaturized. However, the air flow volume that can be produced by thevolume-reduced centrifugal fan is also reduced to largely adverselyaffect the heat removal effect thereof. Further, the miniaturizedcentrifugal fan usually has thin but large-area fan blades, which tendto produce more vibration and noise when the centrifugal fan operates.

As a result, it has become a target of many related manufacturers toeffectively upgrade the performance of the heat radiation unit withoutincreasing the volume thereof.

In brief, the conventional fan module has the following disadvantages:(1) having a relatively big volume; (2) providing low heat dissipationability; and (3) tending to produce vibration and noise during operationthereof.

It is therefore tried by the inventor to develop an improved fan moduleto overcome the drawbacks in the conventional fan module.

SUMMARY OF THE INVENTION

A primary object of the present invention is to effectively solve theabove-mentioned problems by providing a fan module having at least onecross-flow fan, so that the fan module can have reduced volume while thecross-flow fan can create largely increased air flow volume.

Another object of the present invention is to provide a fan module thatprovides upgraded heat dissipation performance and effectively overcomesthe problems of vibration and noise caused by swaying of excessivelylong blades.

To achieve the above and other objects, the fan module according to thepresent invention includes a heat transfer unit, a heat radiation unit,and at least one cross-flow fan. The heat transfer unit has an endattached to a heat source. The heat radiation unit is connected toanother opposite end of the heat transfer unit and has an air-in sideand an air-out side communicable with the air-in side. The cross-flowfan is located against the heat radiation unit, and includes a frame anda centrifugal fan blade assembly. The frame has an air outlet facingtoward the air-in side of the heat radiation unit, a plurality of airinlets, and a plurality of frame sections. The air inlets arerespectively arranged between two adjacent frame sections andcommunicate with the air outlet. The frame sections are respectivelyconfigured as a receiving recess, and the receiving recesses arecommunicable with one another to together define a receiving space. Thereceiving space communicates with the air outlet and the air inlets, andis used to receive the centrifugal fan blade assembly therein.

The fan module with the above design can be used in a limited space, andthe cross-flow fan thereof not only creates largely increased air flowvolume, but also enables effectively reduced volume of the fan module.Further, the problems of vibration and noise caused by the swaying longblades as found in the conventional fan module can also be effectivelyimproved.

BRIEF DESCRIPTION OF THE DRAWINGS

The structure and the technical means adopted by the present inventionto achieve the above and other objects can be best understood byreferring to the following detailed description of the preferredembodiments and the accompanying drawings, wherein

FIG. 1 is an assembled perspective view of a conventional fan module;

FIG. 2A is an exploded perspective view of a fan module according to afirst embodiment of the present invention;

FIG. 2B is an assembled view of FIG. 2A;

FIG. 3A is an exploded perspective view of a fan module according to asecond embodiment of the present invention;

FIG. 3B is an assembled view of FIG. 3A; and

FIG. 4 is an exploded perspective view of a fan module according to athird embodiment of the present invention.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

The present invention will now be described with some preferredembodiments thereof and with reference to the accompanying drawings. Forthe purpose of easy to understand, elements that are the same in thepreferred embodiments are denoted by the same reference numerals.

Please refer to FIGS. 2A and 2B, which are exploded and assembledperspective views, respectively, of a fan module 2 according to a firstembodiment of the present invention. As shown, the fan module 2 in thefirst embodiment includes a heat transfer unit 20, a heat radiation unit21, and at least one cross-flow fan 22.

The heat transfer unit 20 includes a heat-absorbing section 201 and aheat-dissipating section 202. The heat-absorbing section 201 is attachedto a heat source 24, such as a central processing unit, south bridge andnorth bridge chipsets, a graphics chip, or an executing unit. Theheat-absorbing section 201 absorbs heat produced by the heat source 24and the absorbed heat is transferred to the heat-dissipating section202. The heat transfer unit 20 can be a heat pipe, a heat spreader, orany element capable of transferring heat. In the illustrated firstembodiment, the heat transfer unit 20 is configured as a heat pipe butis not necessarily limited thereto.

The heat radiation unit 21 is connected to the heat-dissipating section202 of the heat transfer unit 20, and has an air-in side 213 and anair-out side 214 communicating with the air-in side 213. The heatradiation unit 21 can be a radiating fin assembly, a heat sink, or anyelement capable of radiating heat. In the illustrated first embodiment,the heat radiation unit 21 is configured as a radiating fin assembly butis not necessarily limited thereto. In the first embodiment, the heatradiation unit 21 includes a plurality of radiating fins 211, and anytwo adjacent radiating fins 211 together define an air-guiding passage212 between them. All the air-guiding passages 212 communicate with bothof the air-in side 213 and the air-out side 214.

The cross-flow fan 22 is located against the heat radiation unit 21, andincludes a frame 221 and a centrifugal fan blade assembly 222. The frame221 has an air outlet 2212 facing toward the air-in side 213 of the heatradiation unit 21, a plurality of air inlets 2211, and a plurality offrame sections 2213. The air inlets 2211 are respectively arrangedbetween two adjacent frame sections 2213 and communicate with the airoutlet 2212. The frame sections 2213 are respectively configured as areceiving recess 2213 a, and the receiving recesses 2213 a arecommunicable with one another to together define a receiving space 2214.The receiving space 2214 communicates with the air outlet 2212 and theair inlets 2211, and is used to receive the centrifugal fan bladeassembly 222 therein.

The centrifugal fan blade assembly 222 includes a shaft 2221 and aplurality of impellers 2223. The impellers respectively include aplurality of blades 2223 a circumferentially spaced on the shaft 2221,and are separately received in the receiving recesses 2213 a of theframe sections 2213. The frame 221 further includes a first end plate2215 and a second end plate 2216 that are separately located at twoopposite ends of the frame 221. The first and the second end plate 2215,2216 respectively have a shaft hole 2217 provided thereon. The shaft2221 is sequentially extended through the impellers 2223 with twoopposite ends of the shaft 2221 extending into the two shaft holes 2217.

The cross-flow fan 22 further includes a motor 23, which is arranged toone side of the first end plate 2215 or the second end plate 2216 and isconnected to the centrifugal fan blade assembly 222 for driving thelatter to rotate. When the motor 23 of the cross-flow fan 22 drives thecentrifugal fan blade assembly 222 to rotate, air outside the frame 221is guided into the receiving recesses 2213 a via the air inlets 2211 toflow through the fan impellers 2223 before being blown out of the frame221 via the air outlet 2212 and forced into the heat radiation unit 21via the air-in side 213 thereof. The air forced into the heat radiationunit 21 flows through the air-guiding passages 212 between the radiatingfins 211 toward the air-out side 214. The heat transferred from theheat-dissipating section 202 to the radiating fins 211 will be carriedaway by the air to dissipate into external environment via the air-outside 214, so as to provide enhanced heat dissipation performance andachieve good heat dissipation effect.

With the design of the present invention, the centrifugal fan bladeassembly 222 and the shaft 2221 can still extend transversely in alimited mounting space, so that the cross-flow fan 22 not only createslargely increased air flow volume and accordingly upgraded heatdissipation performance, but also effectively enables reduced volume ofthe fan module 2. Further, the present invention also overcomes theproblems of vibration and noise caused by the swaying long blades in theconventional fan module designed for increasing heat dissipationperformance.

FIGS. 3A and 3B are exploded and assembled perspective views,respectively, of a fan module according to a second embodiment of thepresent invention. As shown, the fan module in the second embodiment isgenerally structurally similar to the first embodiment, except that, inthe second embodiment, the cross-flow fan 22 further includes at leastone side plate 2218, which is arranged at the air outlet 2212 of theframe 221 against the air-in side 213 of the heat radiation unit 21.When the motor 23 of the cross-flow fan 22 drives the centrifugal fanblade assembly 222 to rotate, air outside the frame 221 is guided intothe receiving recesses 2213 a via the air inlets 2211 to flow throughthe fan impellers 2223 before being blown out of the frame 221 andforced into the heat radiation unit 21 via the air-in side 213 thereof.The air forced into the heat radiation unit 21 flows through theair-guiding passages 212 between the radiating fins 211 toward theair-out side 214. Meanwhile, heat will be carried away from theradiating fins 211 by the air to the air-out side 214 and be dissipatedinto external environment, so as to provide enhanced heat dissipationperformance and achieve good heat dissipation effect.

Please refer to FIG. 4 that is an assembled perspective view of a fanmodule according to a third embodiment of the present invention. Asshown, the fan module in the third embodiment is generally structurallysimilar to the previous embodiments, except that, in the thirdembodiment, two or more cross-flow fans 22 are parallelly arranged sideby side. With this arrangement, the heat can also be carried away fromthe radiating fins 211 by air flows to the air-out side 214 of the heatradiation unit 21 and be dissipated into external environment to achievethe purpose of heat dissipation. In the illustrated third embodiment,two cross-flow fans 22 are shown. However, it is understood the numberof the cross-flow fans 22 is not necessarily limited to two.

According to the above description, the fan module of the presentinvention is superior to the conventional one because it has largelyreduced overall volume, eliminates the occurrence of vibration and noiseduring operation, and provides enhanced heat dissipation performance.

The present invention has been described with some preferred embodimentsthereof and it is understood that many changes and modifications in thedescribed embodiments can be carried out without departing from thescope and the spirit of the invention that is intended to be limitedonly by the appended claims.

What is claimed is:
 1. A fan module, comprising: a heat transfer unithaving an end attached to a heat source; a heat radiation unit beingconnected to another opposite end of the heat transfer unit and havingan air-in side and an air-out side communicable with the air-in side;and at least one cross-flow fan being located against the heat radiationunit, and including a frame and a centrifugal fan blade assembly; theframe having an air outlet facing toward the air-in side of the heatradiation unit, a plurality of air inlets, and a plurality of framesections; the air inlets being respectively arranged between twoadjacent frame sections and communicating with the air outlet; the framesections respectively having a receiving recess therein, and thereceiving recesses being communicable with one another to togetherdefine a receiving space; and the receiving space communicating with theair outlet and the air inlets and being used to receive the centrifugalfan blade assembly therein.
 2. The fan module as claimed in claim 1,wherein the frame further includes a first end plate and a second endplate that are separately located at two opposite ends
 3. The fan moduleas claimed in claim 2, wherein the centrifugal fan blade assemblyincludes a shaft and a plurality of impellers; and the shaft beingsequentially extended through the impellers with two opposite ends ofthe shaft extending into the two shaft holes.
 4. The fan module asclaimed in claim 3, wherein the impellers respectively include aplurality of blades, and the blades on each of the impellers beingcircumferentially spaced on the shaft and received in a correspondingone of receiving recesses of the frame sections.
 5. The fan module asclaimed in claim 1, wherein the heat transfer unit further includes aheat-absorbing section and a heat-dissipating section; theheat-absorbing section being attached to the heat source; and the heatradiation unit being connected to the heat-dissipating section.
 6. Thefan module as claimed in claim 1, wherein the cross-flow fan furtherincludes at least one side plate, which is arranged at the air outlet ofthe frame.
 7. The fan module as claimed in claim 1, wherein the heatradiation unit is selected from the group consisting of a radiating finassembly, a heat sink, and any element capable of radiating heat.
 8. Thefan module as claimed in claim 1, wherein the heat transfer unit isselected from the group consisting of a heat pipe, a heat spreader, andany element capable of transferring heat.
 9. The fan module as claimedin claim 7, wherein the heat radiation unit includes a plurality ofradiating fins; any two adjacent ones of the radiating fins togetherdefining an air-guiding passage between them; and the air-guidingpassages communicating with both of the air-in side and the air-outside.
 10. The fan module as claimed in claim 2, wherein the cross-flowfan further includes a motor, which can be arranged to one side of thefirst end plate or the second end plate.